Method and apparatus for cutting a substrate into multiple pieces with a single irradiation of a laser beam

ABSTRACT

A method and apparatus for multiple-cutting a substrate into a plurality of pieces with a single irradiation of a laser beam are disclosed. At least two light reflectivity/transmittance control plates are placed on a path through which the light passes such that light reflectivity/transmittance is varied depending on an angle between the generated light and the plates. Plural surface portions of the substrate are heated simultaneously and are then cooled by a sprayed coolant so that the substrate is cut into a plurality of pieces simultaneously. Resultantly, a cutting time is substantially shortened and the productivity is enhanced.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a technique of cutting asubstrate into multiple pieces using a heat stress, and moreparticularly, to method and apparatus for cutting a substrate intomultiple pieces with irradiation of a laser beam in which a light beam,generated from a single light generating unit with a specific wavelengthand power, is divided into multiple light beams having uniform power,the substrate is locally and rapidly heated by the respective dividedbeams and then rapidly cooled by a coolant, and thereby the substrate isconcurrently cut along plural cutting lines to give multiple pieces.

[0003] 2. Description of the Related Art

[0004] Generally, glass substrate has been widely used for industrial,commercial, and residence applications, to name a few. These glasssubstrates are made from silicon that is a main component. Also, theseglass substrates have a non-crystalline structure that is an inherentcharacteristic of glass. When a minute groove is formed at an edge ofthe glass substrate, the non-crystalline structure acts to trigger anoccurrence of minute cracks by a small impact or a small external force.

[0005] When an external impact or force is applied to the minute cracks,the cracks are propagated along unpredictable directions and thereforean undesired separation occurs in the glass substrate. Thus, there is aproblem in that it is nearly impossible to forecast the direction of thegenerated crack and a portion of the substrate is cut that needs not becut.

[0006] This problem frequently occurs when a diamond cutter is used forthe cutting of a workpiece glass substrate in which a fine groove isformed at the surface of the workpiece glass substrate and then someexternal force is applied. This is because the fine groove formed by thediamond cutter is very rough.

[0007] Thus, in the case that the cut groove of the workpiece glasssubstrate is not smooth, undesired cracks occur additively and the crackpropagates along an undesired direction, which causes a fatal failure.

[0008] Because of these problems, a diamond cutter is mainly used onlyas a cutting tool for cutting a commercial glass substrate, a householdglass substrate, etc., but is subject to many limitations in a technicalfield such as a liquid crystal display (LCD) requiring precise cutting.

[0009] In spite of these limitations, and since methods and apparatusesfor use in the LCD technical field requiring a precise cutting of glasssubstrates are not yet developed, the use of the diamond cutter isinevitable.

[0010] Due to the use of the diamond cutter, there is a problem ofunpredictable cracks and the cracks progating when separating acompleted LCD mother panel into unit panels.

SUMMARY OF THE INVENTION

[0011] Accordingly, it is an object of the present invention to providea method for multiple-cutting a substrate in which a substrate is cut bya heat stress such that an occurrence of cracks is restrained at an edgeof the substrate and therefore crack propagation along an undesireddirection does not occur.

[0012] It is another object of this invention to provide a method formultiple-cutting a substrate in which plural places of the substrate areconcurrently and rapidly heated and then rapidly cooled using a singlelaser beam for heating the substrate, so that the plural places of thesubstrate are concurrently separated.

[0013] It is still another object to provide an apparatus formultiple-cutting a substrate in which a single laser beam for heatingthe substrate is uniformly divided into at least two beams, the dividedbeams concurrently heat at least one prescribed cutting line, the heatedprescribed cutting line is concurrently cooled, so that plural places ofthe substrate are concurrently cut.

[0014] To achieve the aforementioned objects, there is provided a methodof multiple-cutting a substrate. In the above method, a part of anincident light in a first advancing direction is reflected into a secondadvancing direction and the remaining part of the incident lightadvances along the first advancing direction to split the incident lightinto two light beams. The split lights are scanned onto plural selectedpaths of the substrate to locally heat the selected paths of thesubstrate. Thereby, cracks are generated at the heated paths.

[0015] According to another aspect of this invention, there is providedan apparatus for multiple-cutting a substrate into multiple pieces usinga single scanning of a light. The apparatus comprises: a light splittingunit for splitting a light generated from a light generating unit usingat least two light reflectivity/transmittance control plates of whichlight reflectivity/transmittance varies depending on an angle betweenthe generated light and the plates, and for scanning the split lightsonto at least two scanning surface portions to locally heat the scanningsurface portions; and a crack generating unit for generating a crack atthe locally heated scanning surface portions.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The above objects and other advantages of the present inventionwill become more apparent by describing in detail the preferredembodiments thereof with reference to the accompanying drawings.

[0017]FIG. 1 is a schematic view of a light splitting apparatus inaccordance with a preferred embodiment of the present invention.

[0018]FIG. 2 is a perspective view of a light reflectivity/transmittancecontrol plate in accordance with another preferred embodiment of thepresent invention.

[0019]FIG. 3 is a graph showing that the light reflectivity is varieddepending on an angle between the light reflectivity/transmittancecontrol plate and a light.

[0020]FIG. 4 is a schematic view of a substrate cutting apparatus usinga light splitting unit in accordance with another preferred embodimentof the present invention.

[0021]FIG. 5 is a perspective view of a substrate cutting apparatus inaccordance with another preferred embodiment of the present invention.

[0022]FIG. 6 is a schematic view explaining the structure and functionsof the substrate cutting apparatus in accordance with one embodiment ofthe present invention.

[0023]FIGS. 7 and 8 are schematic views for describing a method ofcutting a substrate along an X-axis in accordance with one embodiment ofthe present invention.

[0024]FIGS. 9 and 10 are schematic views for describing a method ofcutting a substrate along a Y-axis in accordance with one embodiment ofthe present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Now, preferred embodiments of the present invention will bedescribed in detail with reference to the accompanying drawings.

[0026] FIGS. 1 to 3 show a constitution of a light multiple-splittingdevice in accordance with a preferred embodiment of the presentinvention.

[0027] As a whole, a light multiple-splitting device 500 includes atleast one light reflectivity/transmittance control plates 510, 520, 530,540, a light incident angle control unit 555 and a base body (not shown)provided with the light reflectivity/transmittance control plate 510,520, 530, 540 and the light incident angle control unit 555.

[0028] Four light reflectivity/transmittance control plates 510, 520,530, 540 are used in the present embodiment.

[0029] Particularly, the light reflectivity/transmittance control plates510, 520, 530, 540 are manufactured to have functions in which when alight 590, having a certain wavelength and intensity, arrives onreflection/transmission surfaces of respective lightreflectivity/transmittance control plates 510, 520, 530, 540, the lightreflectivity/transmittance control plates 510, 520, 530, 540 reflect apart of the light and transmit the remainder of the light.

[0030] As one embodiment, the light reflectivity control plates 510,520, 530, 540 are made of ZnSe to reflect and/or transmit light.

[0031] The reference numeral 580 in FIG. 1 is a light generating unitfor generating a light necessary for cutting a workpiece substrate. Alaser beam having a predetermined wavelength and intensity may be usedas the necessary light.

[0032] At this time, angles θ1, θ2, θ3, θ4 between the light generatedfrom the light generating unit 560 and the reflection/transmissionsurfaces largely affect transmittance and reflectivity in the light.

[0033]FIG. 3 is a graph showing a variation in the reflectivity of alight reflected from the light reflectivity/transmittance control plates510, 620, 630, 540 when the angles θ1, θ2, θ3, θ4, between the lightgenerated from the light generating unit 580 and thereflection/transmission surfaces, are varied.

[0034] In order to obtain results as shown in the graph of FIG. 3, thelight to reflectivity/transmittance control plates 510, 520, 530, 540are made of ZnSe and the necessary light has a wavelength of 10.6 μm.

[0035] Referring to the graph of FIG. 3, in a state that the light ishorizontally scanned, when the reflection/transmission surfaces of thelight reflectivity/transmittance control plates 510, 520, 530, 540 areinclined 70 degrees in the clockwise direction with respect to thehorizontal plane, the reflectivity of the lightreflectivity/transmittance control plates 510, 520, 530, 540 is 0%. Atthis position, the reflectivity of 0% means that the lightreflectivity/transmittance control plates 510, 520, 530, 540 do notreflect the light 500 at all but transmit the light 500 completely.

[0036] Meanwhile, when the inclination of the lightreflectivity/transmittance control plates 510, 520, 530, 540 increasefrom 70 degrees to 90 degrees in the clockwise direction with respect tothe horizontal plane, the reflectivity in the reflection/transmissionsurfaces of the light reflectivity/transmittance control plates 510,520, 530, 540 increases from 0% to about 100% in proportion to theinclination of the light reflectivity/transmittance control plates 510,520, 530, 540. At this point, the reflectivity of 100% means that thelight reflectivity/transmittance control plates 510, 520, 530, 540reflect the light 500 fully, so that the light does not transmit throughthe light reflectivity/transmittance control plates 510, 520, 530, 540at all.

[0037] Resultantly, the graph in FIG. 3 shows that the reflectivity andtransmittance of the light are abruptly varied by controlling only theangles between the light and the light reflectivity/transmittancecontrol plates 510, 520, 530, 640 in such a state in that the same kindof at least two of the light reflectivity/transmittance control platesare positioned on the light path.

[0038] Thus, in the case that the angles are varied; the lightreflectivity/transmittance control plates 510, 520, 530, 540, in whichthe reflectivity and transmittance are varied, are used for splitting asingle light beam into multiple light beams such that the multiple lightbeams are scanned onto a plurality of places. In that case, it ispreferable that the split light beams have an equivalent intensity.

[0039] Hereinafter, there is described in more detail an operationmechanism for splitting the light 500 into multiple light beams having auniform intensity using the light reflectivity/transmittance controlplates 510, 620, 530, 640 and the light incident angle control unit 555with reference to FIGS. 1, 2, and 3.

[0040] As one embodiment, there is described a mechanism for splittingthe light 590 having a power of 400 watts generated from the lightgenerating unit 580 into four light beams each having an intensity of100 watts uniformly at designated places, A, B, C and D using the lightreflectivity/transmittance control plates 510, 520, 530, 540 and theplate rotating unit 550.

[0041] To realize this, the light reflectivity/transmittance controlplates 510, 520, 530, 540 are arranged in series such that the light 590of 400 watts generated from the light generating unit 580 transmits thereflection/transmission surfaces of the light reflectivity/transmittancecontrol plates 510, 520, 530, 540 arranged on an advancing path of thelight.

[0042] Hereinafter, the light reflectivity/transmittance control plates510, 520, 530, 540 are respectively defined as a first lightreflectivity/transmittance control plate 540, a second lightreflectivity/transmittance control plate 530, a third lightreflectivity/transmittance control plate 520, and a fourth lightreflectivity/transmittance control plate 510.

[0043] At this time, as one embodiment of the present invention, thelight generating unit 580 is disposed adjacent to the first lightreflectivity/transmittance control plate 540 while it faces the firstlight reflectivity/transmittance control plate 540.

[0044] Such positions of the light reflectivity/transmittance controlplates 510, 520, 530, 540 allow the incident light 590 to subsequentlypass the first light reflectivity/transmittance control plate 540, thesecond light reflectivity/transmittance control plate 530, and the thirdlight reflectivity/transmittance control plate 520, and to arrive at thefourth light reflectivity/transmittance control plate 510.

[0045] Hereinafter, there is described a mechanism in which the incidentlight 590 is uniformly split through the first lightreflectivity/transmittance control plate 540, the second lightreflectivity/transmittance control plate 530, the third lightreflectivity/transmittance control plate 520, and the fourth lightreflectivity/transmittance control plate 510.

[0046] As one embodiment, the light generating unit 580 generates alight 590 having a power of 400 watts and the lightreflectivity/transmittance control plate is comprised of four plates510, 520, 530, 540 of first, second, third and fourth lightreflectivity/transmittance control plates.

[0047] First, with reference to FIG. 1, in order for a light having apower of 100 watts to be irradiated at the point D from the first lightreflectivity/transmittance control plate 540, it is required that theincident light of 100 watts be reflected by the first lightreflectivity/transmittance control plate 540 and, further that theremaining light of 300 watts be transmitted to the first lightreflectivity/transmittance control plate 540. In other words, this meansthat the first light reflectivity/transmittance control plate 540reflects one-fourth (25%),of a total amount of the incident light 590having the power of 400 watts and transmits the remaining three-fourths(75%) of the total amount of the light 590.

[0048] To realize this, the reflectivity of the first lightreflectivity/transmittance control plate 540 is controlled depending onthe relationship shown in the graph of FIG. 3, thereby having a slopeangle of θ1. The angle of θ1 is obtained from the graph in FIG. 3. Inother words, in FIG. 3, a point where the reflectivity of about 25%meets the curve corresponds to θ1.

[0049] Similarly, the remaining light of 300 watts in the light 690 of400 watts generated from the light generating unit 580 is incident intothe second reflectivity/transmittance control plate 530. At that point,the second light reflectivity/transmittance control plate 530 reflectsonly one-third (33.3%) of a total amount of the incident light 590 of300 watts and transmits the remaining two-thirds (66.7%) of 200 watts,so that the reflected light of 100 watts is scanned at the point C.

[0050] To realize this, it is required that the second lightreflectivity/transmittance control plate 530 should have a reflectivityof one-third (about 33.3%) and a transmittance of two-thirds (about66.7%).

[0051] Similarly, the second light reflectivity/transmittance controlplate 530 should be inclined by an angle of θ2 in the counterclockwisedirection with respect to the horizontal plane. Like that of θ1, theangle of θ2 is obtained from the graph of FIG. 3. Specifically in thegraph of FIG. 3, a point where the reflectivity of about 33.3% meets thecurve corresponds to θ2.

[0052] While the light of 100 watts is scanned at the point C throughthe second light reflectivity/transmittance control plate 530, theremaining light of 200 watts is incident into the third lightreflectivity/transmittance control plate 520.

[0053] Again, since the third right reflectivity/transmittance controlplate 520 scans the light of 100 watts at the point B among the totalincident light amount of 200 watts, it should have a reflectivity of 50%and a transmittance of 50%.

[0054] To realize this, it is required that the third lightreflectivity/transmittance control plate 520 be inclined by an angle ofθ3 in the counterclockwise direction with respect to the horizontalplane. Like the angles of θ1 and θ2, the angle of θ3 is also obtainedfrom the graph of FIG. 3. Specifically, in FIG. 3, a point where thereflectivity of 50% meets the curve corresponds to θ3.

[0055] While the light of 100 watts is scanned at the point B throughthe third light reflectivity/transmittance control plate 520, theremaining light of 100 watts is incident into the fourth lightreflectivity/transmittance control plate 510.

[0056] Similarly, the fourth light reflectivity/transmittance controlplate 510 has the reflectivity of 100%. This is because all of theincident light amount of 100 watts has to be reflected by the fourthlight reflectivity/transmittance control plate 510 such that the lightamount of 100 watts arrives at the point A.

[0057] To realize this, it is required that the fourth lightreflectivity/transmittance control plate 510 be inclined by an angle of64 in the counterclockwise direction with respect to the horizontalplane. As in the angles of θ1, θ2 and θ3, the angle of θ4 is alsoobtained from the graph of FIG. 3. Specifically, in the graph of FIG. 3,a point where the reflectivity of 100% meets the curve corresponds toθ4.

[0058] Thus, in order to allow plural light beams having the same powerto be scanned at plural places by controlling the reflectivity of theincident light 590, which is incident into the reflection/transmissionsurface of the light reflectivity/transmittance control plates 510, 520,530, 540, as one embodiment, the light reflectivity/transmittancecontrol plates 510, 520, 530, 540 are constituted to include lightmultiple division lenses 510 a, 520 a, 530 a, 540 a and a light incidentangle control unit 555 coupled to the light multiple division lenses 510a, 520 a, 530 a, 540 a, as shown in FIG. 2.

[0059] The light incident angle control unit 555 comprises a rotationalshaft 512, 522, 532, 542, fixedly coupled to a selected portion of thecircumference of the light multiple division lenses 510 a, 520 a, 530 a,540 a, and a rotational motor 550, coupled to the rotational shaft 512,522, 532, 542, for rotating the coupled rotational shaft 512, 522, 532,542 in the clockwise or counterclockwise direction.

[0060] Hereinafter, described is a detailed constitution of theworkpiece substrate multiple cutting apparatus to which the lightmultiple-splitting apparatus 500 having the aforementioned constitutionand operation mechanism is applied with reference to the accompanyingdrawings of FIGS. 4, 5 and 6.

[0061] Referring to FIGS. 4 and 5, a substrate multiple-cuttingapparatus 900 includes a light generating unit 100, a first lightmultiple-splitting unit 300, a crack generating unit 400, a second lightmultiple-splitting unit 600 and a mother substrate-transferring unit750.

[0062] Specifically, the mother substrate-transferring unit 750 includesa transferring body 754 and a transferring body driving unit 762. Morespecifically, the transferring body 754 has a sufficient planar area tomount an assembled workpiece substrate 700 thereon. On the transferringbody 754, the transferring body driving unit 752 is established totransfer the transferring body 754 along the x-axis direction of x-y-zcoordinates.

[0063] Meanwhile, at places spaced apart by a certain distance outwardlyalong the z-axis direction from the mother substrate transferring unit750, there are disposed the light generating unit 100 and a coolantsupplying unit 200 for supplying a coolant to the crack generating unit400. The light generating unit 100 and the coolant supplying unit 200are coupled to their respective transferring units 110 and 255.

[0064] The transferring units 110 and 255 function to reciprocate thelight generating unit 100 and the coolant supplying unit 200 at the samevelocity in a direction parallel to the x-axis.

[0065] Meanwhile, the light generating unit 100 irradiates two lightbeams 810 and 803 toward the coolant supplying unit 200 from twoportions thereof as shown in FIG. 6. Hereinafter, one of the two lightbeams as irradiated is defined as a first light beam 803 and the otheris defined as a second light beam 801.

[0066] On a path through which the first light beam 803 passes, there isdisposed a first light multiple-splitting unit 300, and on a paththrough which the second light beam 801, there is disposed a secondlight multiple-splitting unit 600.

[0067] Particularly, the first light multiple-splitting unit 300includes plural light reflectivity/transmittance control plates 310,320, 330, 340, plural plate rotating units 312, 322, 332, 342 and aplate fixing case 380 as shown in FIG. 5.

[0068] First, the plate fixing case 380 has a through hole formed alongits length direction and it is disposed between the light generatingunit 100 and the coolant supplying unit 200. The first light beam 803passes through the through hole of the plate fixing case 380.

[0069] Inside the plate fixing case 380, at least two lightreflectivity/transmittance control plates are established. As oneembodiment, FIG. 6 shows that four light reflectivity/transmittancecontrol plates 310, 320, 330, 340 are established.

[0070] The light reflectivity/transmittance control plates 310, 320,330, 340 have a close relationship with the position of an LCD unit cell710 formed in the assembled workpiece mother substrate 700.Particularly, the LCD unit cell 710 has two edges in the x-axisdirection and two edges in the y-axis direction. Thus, in order toseparate the LCD unit cell 710 from the assembled workpiece mothersubstrate 700, it is necessary to cut two x-directional lines and twoy-directional lines.

[0071] At that point, in order to cut the two x-directional lines or thetwo y-directional lines using a single light beam at the same time, itis necessary to use two light reflectivity/transmittance control plates.

[0072] Thus, in order to cut four x-directional prescribed lines or foury-directional prescribed lines of four LCD unit cells 710 in a matrixconfiguration of 2 by 2 from the assembled workpiece mother substrate700 using a single light beam at the same time, it is necessary to usefour light reflectivity/transmittance control plates.

[0073] Similarly, an interval between the lightreflectivity/transmittance control plates 310, 320, 330, 340 isprecisely controlled such that the split light beams correspond to thefour x-directional prescribed lines or four y-directional prescribedlines precisely

[0074] Meanwhile, the second light multiples-splitting unit 600 includesplural light reflectivity/transmittance control plates 610, 620, 630,640, plural plate rotating units 612, 622, 632, 642 and a plate fixingcase 680 as shown in FIGS. 5 and 6.

[0075] First, the plate fixing case 680 has a through hole formed alongits length direction and it is disposed between the light generatingunit 100 and the coolant supplying unit 200. The second light beam 801passes through the through hole of the plate fixing case 680.

[0076] Inside the plate fixing case 680, at least two lightreflectivity/transmittance control plates are established. As oneembodiment, FIG. 6 shows that four light reflectivity/transmittancecontrol plates 610, 620, 630, 640 are established.

[0077] In the same manner as in the first lightreflectivity/transmittance control plates 310, 320, 330, 340, the secondlight reflectivity/transmittance control plates 610, 620, 630, 640 areestablished to have a number sufficient to cut either four x-directionalprescribed lines or four y-directional prescribed lines at the sametime.

[0078] Meanwhile, between the first light multiple-splitting unit 300and the second light multiple light-splitting unit 600, there isdisposed the crack generating unit 400 The crack generating unit 400functions to inject coolant onto locally heated prescribed lines of theassembled workpiece mother substrate 700.

[0079] To realize this, the crack generating unit 400 includes a coolantsupply pipe 410 for transferring a coolant from the coolant supplyingunit 200 to a position at which the coolant is being sprayed, and acoolant spraying nozzle 412, 422, 432, 442 for spraying the coolanttransferred from the coolant supply pipe 410 onto the locally heatedposition.

[0080] Hereinafter, there is described a singulation method of the LCDunit cell from the assembled workpiece mother substrate 700 using thesubstrate multiple-splitting apparatus 900 in accordance with oneembodiment of the present invention with reference to the accompanyingdrawings of FIGS. 7, 8, 9, and 10.

[0081] First, as shown in FIG. 7, in a state that a first large-sizedmother glass substrate 720 for a thin film transistor (TFT) substrateand a second large-sized mother glass substrate 730 for a color filtersubstrate are aligned and attached with facing each other, and then aliquid crystal injecting process is completed, the attached workpiecemother substrate 700 is mounted on the transferring body 754 of themother substrate transferring unit 750 (see FIG. 5) by a mother boardtransfer (not shown).

[0082] After that, the first light multiple-splitting unit 300, thecrack generating unit 400 and the second light multiple-splitting unit600 are aligned with at least two positions on a one-sided surface ofthe assembled workpiece mother substrate 700.

[0083] Afterwards, as shown in FIG. 7, the first light beam 803 issupplied into the first light multiple-splitting unit 300. The firstlight multiple-splitting unit 300 splits the first light beam 803 intouniform multiple light beams each having the same intensity and scansthe split light beams onto the positions which are being cut so that thescanned portions are rapidly heated.

[0084] Thereafter, the rapidly heated portions are rapidly cooled by acoolant 802 sprayed from the crack generating unit 400, which isestablished to the rear of the first light multiple-splitting unit 300,so that a scribe crack is generated to a predetermined depth from theupper surface of the rapidly heated portion.

[0085] After that, the second light beam 801, split by the second lightmultiple-splitting unit 600, is irradiated onto the scribe crack toheat-expand the scribe crack portion locally, rapidly, so that thescribe crack portion is completely separated by the heat expansion.Thus, the x-directional prescribed lines 701 of the LCD unit cells 710in the assembled workpiece mother substrate 700 are all cut.

[0086] Thereafter, as shown in FIGS. 9 and 10, in a state that the oncesplit workpiece mother substrate is rotated horizontally by 90 degrees,y-directional prescribed lines 702 are cut by the first split light beam803, the coolant 802 and the second split light beam 801, so that an LCDpanel is manufactured.

[0087] Afterwards, the LCD panel is transferred into an LCD panelassembly manufacturing process and thus an LCD panel assembly ismanufactured.

[0088] As described previously in detail according to the presentinvention, plural LCD unit cells formed in a single large-size motherglass substrate are concurrently cut by splitting a single incidentlight into plural light beams, so that time necessary for thesingulation of the LCD unit from the mother glass substrate issubstantially shortened.

[0089] Further, a single incident light is split into plural light beamsto perform a cutting process at plural places, so that an apparatus forcutting LCD unit cells from the mother substrate is simplified.

[0090] While the present invention has been described in detail, itshould be understood that various changes, substitutions and alterationscan be made hereto without departing from the spirit and scope of theinvention as defined by the appended claims.

1-8. (Cancelled)
 9. A cutting device comprising: means for generating afirst incident light in a first direction; means for splitting the firstincident light into a plurality of lights and directing the plurality oflights toward a target object; and means for moving the means forsplitting in a second direction different form the first direction suchthat the plurality of lights are scanned along a plurality ofpredetermined paths on the target object.
 10. The cutting device ofclaim 9, wherein the second direction is perpendicular to the firstdirection.